Kolkata Metro has constructed the first-ever transport tunnel in the country which will pass through underwater. The East-West Metro corridor will pass through under Hooghly river and it will become the first such river crossing in the country.
Two tunnels are being constructed on the up and down line, which is about 1.4 kilometres long. The width of the Hooghly river here is about 520 meters and this tunnel passes through the bottom of the river bottom.
Kolkata metro is spending Rs 8,572 crore on this entire project.